Question

The connecting link between Annelids and Mollusks is:

• A. Peripatus
• B. Neopilina
• C. Proterospongia
• D. Archaeopteryx

Answer 1

The correct option is B

Neopilina

The correct option is option B.

Explanation of the correct option:

1. The body of Neopilina is oval in shape.
2. It has five pairs of nephridiospores and five pairs of pectinate gills
3. Also, there are five pairs of shell muscles.
4. This arrangement is similar to that of the phylum Annelida.
5. It exhibits the annelid ancestry of mollusks and hence is said to be a connecting link between Annelids and Mollusks.

Explanation of the incorrect options:

Option A:

1. Peripatus belongs to the genus Onychophora.
2. It is mainly comprised of velvet worms.
3. Their body is elongated consisting of 14 to 44 trunks segments, each segment having a pair of short legs.
4. It is a connecting link between Annelida and Arthropoda.

Option C:

1. It is a single-celled aquatic organism that forms colonies.
2. The cell body is 5-10$\mu m$ in diameter and has a flagellum.
3. It is a connecting link between the phylum Protozoa and Porifera.

Option D:

1. It is a fossil bird.
2. It has both reptile-like features as well as avian features.
3. Therefore, it is regarded as a connecting link between reptiles and birds.

Final answer: The connecting link between annelids and mollusks is Neopilina.